A cell-based electrochemical biosensor was developed to determine the antioxidant activity of Asp-Leu-Glu-Glu (DLEE) isolated from dry-cured Chinese Xuanwei ham. A platinized gold electrode (Pt NPs/GE) covered with silver nanowires (Ag NWs) was fabricated to detect H₂O₂ using redox signaling via cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). Under optimal condition, the detection limit of the modified electrode was 0.12 μM with a linear relationship from 0.2 to 2 μM, which showed relatively outstanding catalytic effects towards the reduction of H₂O₂. Furthermore, the generation of reactive oxygen species (ROS) in the cell can be used to indirectly assess changes in intercellular oxidative stress by detecting variations in electrochemical signals. A 3D cell culture of alginate/graphene oxide (NaAlg/GO) was used to encapsulate and immobilize Caco-2 cells. Based on ROS generation and electrochemical results, we found that DLEE could effectively reduce oxidative stress level in Caco-2 cells under external stimulation. DLEE showed high antioxidant activity with a relative antioxidant capacity (RAC) rate of 88.17% at 1.5 mg/mL. Finally, an efficient electrochemical biosensor was established using the active 3D Caco-2 cell platform. This system is sensitive and simple to operate with the property to evaluate the antioxidant activity of peptides by the detection of H₂O₂ in cell membrane. In summary, this work describes a new method for assessing antioxidant capacity of peptide DLEE using cell-based electrochemical signaling with a rapid screening pattern.

开发了一种基于细胞的电化学生物传感器，以确定从干腌宣宣火腿中分离得到的Asp-Leu-Glu-Glu（DLEE）的抗氧化活性。制备了覆盖有银纳米线（Ag NWs）的镀金金电极（Pt NPs / GE），以通过循环伏安法（CV），差分脉冲伏安法（DPV）和电化学阻抗谱（EIS）使用氧化还原信号检测H ₂ O _2。。在最佳条件下，修饰电极的检出限为0.12μM，线性关系为0.2至2μM，显示出对H ₂ O ₂还原的相对优异的催化作用。。此外，通过检测电化学信号的变化，可将细胞中活性氧（ROS）的生成用于间接评估细胞间氧化应激的变化。海藻酸盐/氧化石墨烯（NaAlg / GO）的3D细胞培养用于封装和固定Caco-2细胞。基于活性氧的产生和电化学结果，我们发现DLEE可以有效降低外界刺激下Caco-2细胞的氧化应激水平。DLEE在1.5 mg / mL时显示出高抗氧化活性，相对抗氧化能力（RAC）率为88.17％。最后，使用有源3D Caco-2细胞平台建立了有效的电化学生物传感器。该系统灵敏且易于操作，具有通过检测H ₂来评估肽的抗氧化活性的特性细胞膜中的O ₂。总而言之，这项工作描述了一种新的方法，该方法使用具有快速筛选模式的基于细胞的电化学信号来评估肽DLEE的抗氧化能力。